LED T-shirt

Step 1: LED T-shirt

T-shirts may be a staple for just about everybody, but they are kind of boring. Time to make a custom T-shirt using commonly found electronics and fabric! You can easily use the methods shown here to make your own custom shirt in with just about any lighting scheme you can think of. Best of all, you'll be able to supply your own light when it's dark, perfect for parties or when the power goes out!

This shirt uses a cheap rechargeable key chain flashlight for the LED's and power supply, and fabric scraps for the embellishments. This project is simple enough for anyone to try, but does require some patience. Trust me, when you see your results come to life it's all worth it. Ready to make your own?

Enough talk, let's light up a T-shirt!

Step 2: tools + materials

Step 3: designing the shirt / glue down + sew

First, you first need to decide what you want your design to be. Maybe you want to make a light-up starry sky, or add lights to your favourite robot. Whatever you decide, plan it out first and determine how many lights you want to use and how you're going to run the wires. For my design I decided to keep it simple: the entire shirt is a face, has a zipper for a mouth that opens, and two light clusters representing eyes.

*author's note*
T-shirt cotton does not leave nice edges after it's been cut, it curls and is frustrating to deal with. To make my life easier I used fabric glue (it's like really goopy white glue) to hold my pieces in place, they were sewed on later. My fabric glue boasted that it was "safe to use on most fabrics and could be washed after application had dried"; this statement was mostly true, but I really wouldn't count on it.
Sew your glued portions to ensure security between fabric and t-shirt.

glue eyes:
To make the crossed-out eyes I made 4 even rectangles out of scrap fabric, then folded over the edges and used fabric glue to hold in place. The rectangles were placed overlapping at 90 degrees, two for each eye. More fabric glue was used to hold the eyes in place.

glue mouth:
An opening was cut along the front of the shirt the length of the zipper. The opening edges were folded inside the shirt and glued down. Then the zipper was glued on to the folded edges of the opening. Wait until the glue has dried for about an hour before moving on.

Once the glue has dried you can add the pink backing. This part can be finicky, which is why the glue needed to dry.
To really sell this zipper-mouth on this shirt there needs to be a fleshy pink backing viewable when the zipper is open. Extra pink fabric was used so that when the zipper was opened the shirt would sag some and expose the pink fabric.

sew everything:
Once you pieces have been placed and the glue has dried you can sew everything in place. I chose another contrasting colour to my shirt and scrap fabric, and a zig-zag stitch, to make everything pop!

After designing your shirt and sewing everything in place it's time to set it aside and work on the electronics.

Step 4: break down flashlight / trim housing

I wanted my shirt to not only light up, but be able to charge up on the go. I had originally planned on using a solar garden light (inexpensively found at most Dollar Stores), but I managed to find this solar flashlight which was much smaller and had a brighter light (also at the Dollar Store).

Using a flat head screwdriver I was able to easily pry apart the case and expose the solar panel and circuit board inside. The plastic nub on the flashlight housing for the key chain was no longer required and was trimmed using a sharp utility knife flush with the housing sides.

Step 5: hack solar circuit

For this project I wanted two sets of LED clusters run in parallel, but the PCB that came with my solar flashlight was divided into 3 LED's in parallel. To fix this, I removed the LED's from the board and then bridged the positives together with a paperclip soldered in place; ditto with the negatives.

Step 6: light clusters

soldering:
I wanted this shirt to have illuminated eyes, but there's loads of options on how to divide and spread your lights. Just make sure you've calculated the right load for your battery.

For my light clusters, I used 3 LED's for each eye. The LED's were held together using masking tape and arranged with the negative terminals in the middle. Solder the lights together leaving a long length of wire/conductive thread on each terminal. After wiring the exposed wired back of each LED cluster was encased in hot glue.

fabric backing:
In order to have these lights stay sticking out of the shirt they need to be held in place, but also need to be removable when the shirt needs to be washed. To solve this, hook and loop fasteners (velcro or other) are used. Cut an opening in the 'hook' side of the fastener approximately the same size as the light cluster and corresponding openings in the 'loop' fasteners. Place the LED cluster through the opening, then use hot glue to sandwich the LED and hook fastener to a scrap piece of denim (the denim will help protect the wearer from chafing). Trim to remove excess material.
The 'loop' fastener is placed on the inside of the shirt in the location of the light cluster. I glued mine in place and sewed on by hand to ensure it was secure. We'll create openings for the LED's in the next step.

Repeat for all light clusters.

Step 7: shirt openings

Solar panel opening:
The flashlight casing easily snaps back together. I wanted to use this aspect of the flashlight casing to affix it to the t-shirt. After locating the position I wanted the solar panel on the back of the shirt a small opening was cut, then reinforced with a scrap piece of denim slightly larger than the opening;  more fabric glue was used. This denim will help ease the stress on the t-shirt and prevent the opening from tearing.

After creating the solar panel opening several smaller holes were made with a hot soldering iron, these small holes will allow the posts on one half of the flashlight housing to dock with it's mate on the other side, through the shirt. The solar panel will now face the outside (and the sun), with the button located on the inside of the shirt.

LED openings:
Two opening were created on the front side of the shirt, in the middle of each eye. A hot soldering iron was used to burn the opening, then sharp scissors were used to clean up loose edges on the opening. Your LED cluster should now fit through the opening with the fabric backing holding it to the fastener.

Step 8: wear and shine!

That's it, you're now ready to wear you funky LED T-shirt.
The wires/conductive thread was fed over each shoulder and connect the LED clusters to the solar panel and battery back.

With your light-up shirt you're ready to exploring in the dark when it's late or when the power goes out. Your solar battery pack makes sure you're always charged and ready for the darkness. The zipper mouth, well you can keep small items in there; or make it larger and make it a pouch to keep cookies in!

Have fun!